What test is used to measure the impact resistance of a 3D printed part?

Several tests can be used to measure the impact resistance of a 3D printed part, but the Charpy impact test and the Izod impact test are the most common. These tests involve striking a notched specimen with a pendulum of known energy. The amount of energy absorbed by the specimen before it fractures is a measure of its impact resistance. The Charpy test typically involves supporting the specimen horizontally and striking it on the opposite face of the notch, while the Izod test involves clamping the specimen vertically and striking it above the notch. The results are usually reported in units of energy per unit area, such as Joules per square meter (J/m²). These tests are standardized under ASTM (American Society for Testing and Materials) and ISO (International Organization for Standardization) standards, ensuring consistent testing procedures and comparable results across different materials and labs. The specific test chosen often depends on the geometry of the part and the desired information.